When Syphilis Mimics Oral Squamous Cell Carcinoma

  • by AGD Staff
  • Mar 31, 2025
3-24-25_GenDentClinicians may not always consider the inclusion of sexually transmitted infections in their differential diagnosis in older adults. The aim of this article is to extend the knowledge of an unusual presentation of oral syphilis. 

A 62-year-old man sought evaluation for a severely painful, deeply ulcerated lesion on the floor of the mouth. Although two previous oral biopsies revealed nonspecific ulceration with inflammation, a head and neck surgeon had advocated resection of the floor of the mouth due to a high suspicion for malignancy. One month after the outbreak of the oral ulceration, the patient developed a widespread cutaneous rash, and cutaneous biopsy and serologic studies confirmed a diagnosis of syphilis. After 3 weeks of doxycycline treatment, there was nearly complete resolution of the oral and cutaneous lesions. 

Early diagnosis of syphilis may lead to timely pharmaceutical intervention, avoidance of unnecessary surgical intervention, improved patient outcomes and reduction of disease transmission.

Learn more in the March/April issue.